Graph Vector Function r(t) = sin t (i) + cos t (j) + t (k)

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The vector function r(t) = sin t (i) + cos t (j) + t (k) describes a three-dimensional curve. The x and y components represent a circular motion in the XY plane, as shown by the equation x^2 + y^2 = 1. The z component, which is linear with respect to t, indicates that the graph extends vertically along the Z-axis. This results in a helical shape, resembling a spring or coil. The discussion confirms the understanding of the graph's characteristics and its classification as a helix.
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Homework Statement



r(t) = sin t (i) + cos t (j) + t (k)

(a) Graph the vector function

i = x

j = y

k = z


Is this correct.

Since t is in the Z direction. I'm going to assume that this graph is parallel to the XY plane.


Now I'll take

x = sin t
y = cost t

Then if you square both of these functions.

so then we get x^2 + y^2 = (sin t) ^ 2 + (cos t) ^ 2

Then this becomes x^2 + y ^2 = 1

So it's a circle. Right. Is it going to be a spring or coil on the z - axis.
 
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Yep, that's right. The term for such a graph is a "helix".
 
Oh ok. Thanks.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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